JP2002323836A - Cleaning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cleaning ability of a cleaning device that uses a cleaning blade by scraping a sticking material on an image carrier by an auxiliary cleaning means which does not have a mechanical structure, and to constituted the device so that the load of the cleaning blade on the image carrier is reduced. SOLUTION: By externally adding and mixing ultra fine particles of high adhesion and small grain-sized fine particles of high cohesion to spherical developer, a flocculating agent layer is formed on the upstream side of the contact part where the cleaning blade comes into contact with the image carrier in the image carrier moving direction, and the contact pressure of the cleaning blade with the image carrier is made lower, and also, the contact width is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device for an image forming apparatus using an electrophotographic process, such as an electrostatic copying machine and a printer.

[0002]

2. Description of the Related Art In the above-described cleaning device of an image forming apparatus, it is difficult to transfer all the developer of a developer image formed on the surface of an image carrier to a transfer material during transfer. It is inevitable that the agent remains on the image carrier. Further, transfer material powder and the like generated when the transfer material comes into contact with the image carrier also adhere to the image carrier. Therefore, it is necessary to sufficiently clean the developer and the transfer material powder remaining on the image carrier even after the transfer (hereinafter, these are collectively referred to as a transfer residual developer) every time the transfer is performed.

Various cleaning means have been proposed for this purpose. However, the edge of a cleaning blade made of an elastic material such as rubber is brought into contact with an image carrier to scrape off and remove the transfer residual developer. It is well known that such a method is already widely used because of its simple structure, low cost, and excellent function of removing the transfer residual developer.

FIG. 2 shows an example of a known cleaning device, which has an axis in a direction perpendicular to the plane of the paper and has a charger, a developing device, a transfer means and the like arranged around the device (not shown in the figure). A) A cleaning device is arranged close to the rotating cylindrical image carrier 1.

The cleaning device has a casing 3 having an opening in one direction of the image carrier 1 and a cleaning blade 2 made of urethane rubber or the like in the opening.
One edge of the blade is in contact with the image carrier 1, and the untransferred developer 5 generated at a transfer site (not shown) removes the edge of the cleaning blade 2. When it reaches the site, it is scraped off.

Further, the transfer residual developer 5 that has been scraped off and accumulated by the cleaning blade 2 is again supplied to the edge of the cleaning blade 2 by rotation of the image carrier 1, thereby causing friction due to the presence of powder. Due to the decrease in the force, it is possible to obtain a stable and good cleaning performance without turning up the cleaning blade 2 or the like.

Further, a spherical developer 5 obtained by a suspension polymerization method or the like is used to obtain a high-definition image because the particle diameter can be reduced and the distribution thereof can be uniform. This is because the image carrier 1 is further spherical.
This is because there is an advantage that the amount of the developer 5 remaining after the transfer is reduced because the contact surface area with the developer is reduced and the releasability is improved. As used herein, the term “spherical developer” refers to a developer in which the ratio of the average minor axis to the average major axis of the particles is closer to a perfect circle than 0.90.

[0008]

However, in the case of the above-mentioned apparatus, the spherical developer 5 is more difficult to be scraped off from the image carrier 1 by the cleaning blade 2 than the developer obtained by the usual pulverizing method. is there. for that reason,
The contact pressure of the cleaning blade 2 on the image carrier 1 must be increased in order to improve the scraping property of the cleaning blade 2. However, the increase in the contact pressure increases the problem that damage and abrasion of the image carrier 1 are promoted. Occurs.

The image carrier 1 and the cleaning blade 2 are
If there is nothing intervening in the contact portion, the adhesive force increases, and when the image carrier 1 is rotationally driven, an unstable contact state (blade turning) is caused by frictional force. When a powder, which is a developer used for image formation, intervenes there, the frictional force at the contact portion is reduced, and a stable contact state can be maintained.

The blade turn-up phenomenon is a problem that tends to occur in a cleaning device in which the cleaning blade 2 contacts the counter in the direction opposite to the rotation direction of the image carrier 1, that is, the counter. When the cleaning blade 2, which is a rubber material, is pressed against the image carrier 1, the pressing force is concentrated on the tip of the cleaning blade 2 in a contact portion (hereinafter, blade nip) between the image carrier 1 and the cleaning blade 2. Since the pressure is applied only to the tip, the transfer residual developer 5 riding on the image carrier 1 cannot enter the blade nip and can be effectively scraped.
Due to the frictional force between the image carrier 1 and the cleaning blade 2, the high pressure portion at the tip of the blade nip is dragged and bitten. If the state of the compression advances, the cleaning blade 2 buckles and turns over, loses the cleaning ability, and becomes a so-called blade-turned state. Therefore, if the powder is sandwiched in a state where it is compressed to the extent that it is not turned over, a very small amount of powder enters the inside of the blade nip and reduces the true contact area of the blade nip, so that the frictional force decreases and the blade does not turn.

However, in order for the cleaning blade 2 to stably contact the image carrier 1, a stable amount of powder must always be supplied in the vicinity of the blade nip. Since the amount of the transfer residual developer 5 changes depending on the density, a fixed amount of the developer 5 is always used.
Is difficult to supply to the edge of the cleaning blade 2 to maintain stable contact. For example, if a large number of documents having a low image density ratio are image-formed, the amount of the developer 5 supplied to the edge of the cleaning blade 2 becomes insufficient. Thereby, the image carrier 1 and the cleaning blade 2
The effect of lowering the frictional force due to the contact with the toner due to the presence of the fine particles is eliminated, and the cleaning blade 2 is
In addition, it is not only impossible to turn up in the moving direction and to scrape off the deposits on the image carrier 1, but also the image carrier 1 may be damaged by applying an impact force. Conversely, a large amount of the developer 5 or the like is supplied to the cleaning device due to the formation of a large number of documents having a high image density ratio or the untransferred developer 5 being supplied to the cleaning device due to sudden stoppage of the device. When it comes, it becomes impossible to scrape off with the cleaning blade 2, and the developer 5 slips through the cleaning device, so that the cleaning ability is reduced.

Further, as described above, the cleaning blade 2 cannot stably contact the driving of the image carrier 1 without the presence of the powder, but this is because the developer is only sandwiched between the blade nips. In addition, a cleaning failure such as fusing the developer 5 to the image carrier 1 or pushing up the blade nip to cause the developer 5 to slip through the cleaning device occurs, thereby contaminating the charger disposed downstream of the cleaning device. I do. Further, there arises a problem that the developer 5 sandwiched inside the abutment of the cleaning blade 2 damages the image carrier 1.

Therefore, in order to maintain the cleaning ability, which is the ability to remove the deposits on the image carrier 1, particles for stably stabilizing the contact of the cleaning blade 2 are supplied to the edge of the cleaning blade 2. There is a need to. For this purpose, a cleaning roller, a cleaning brush, or the like is disposed upstream of the cleaning blade 2 as a cleaning auxiliary means, and the amount of the developer 5 supplied to the edge of the cleaning blade 2 is relatively reduced so as to form an image. Conventionally, a configuration that does not depend on the fluctuation of the density of the chromium is used. However, not only is the configuration complicated, but also when the system of the cylindrical image carrier 1 is small,
There may be a case where there is no space for disposing such cleaning assisting means around the image carrier 1. In this case, the cleaning property must be maintained by a method such as increasing the pressing force of the cleaning blade 2 against the image carrier 1. However, as a result, deterioration of the image carrier 1 due to rubbing damage or the like increases, which is a factor of shortening the life of the image carrier 1.

[0014]

SUMMARY OF THE INVENTION The present invention has been made in order to cope with such a situation, and has a structure in which a cleaning blade 2 scrapes off an image carrier 1 in a cleaning device of an image forming apparatus. In the above, particles having high cohesiveness (coagulant) having a volume average particle size of about 10% than the developer 5 and adhesive properties having a volume average particle size of about 0.1% than the developer 5 Strong particles (adhesive)
Is used, and the developer 5 is used.

As described above, since the blade nip is compressed by the frictional force between the image carrier 1 and the cleaning blade 2, the tip of the cleaning blade 2 is slightly distorted to form a wedge-shaped space. This compression state is a transitional state until the blade is turned up, and is very unstable. However, the adhesive having a very small particle diameter easily penetrates into the blade nip with respect to the developer, and the strength of the adhesive causes the cleaning blade 2 to be more effectively compressed to interpose the next particles. Stabilizes the formation of wedge-shaped spaces. However, the adhesive alone does not have the effect of eliminating the curl of the blade itself due to its own adhesive strength and small particle size.

In the space above the wedge, a coagulant externally added and mixed in the developer 5 is selectively stored. This is because smaller particles are more likely to fill smaller spaces,
Here, when the coagulant having a smaller particle diameter than the developer accumulates and is filled in the wedge-shaped space by the cohesive force, the developer cannot enter. Further, a very small amount of the coagulant enters the blade nip little by little and improves the slidability of the cleaning blade 2 so that a stable contact state of the cleaning blade 2 can be maintained. The particles that pass through to stabilize the rubbing of the cleaning blade 2 have a small particle size and a small amount, so that they do not affect image formation.

Specifically, a developer having a particle size of 4 to 10 μm generally has a charge amount of about several tens μC / g and low cohesiveness.
The developer used in the present invention is a true spherical developer obtained by a suspension polymerization method or the like. In such a developer, the cleaning blade 2 is attached to the edge of the cleaning blade 2 near the contact portion. If a gap of about the particle size is generated due to the magnitude of the distortion generated when being dragged by the rotation, it sinks in. Once sneaked, the developer is sandwiched inside the blade nip, but because of its true spherical shape, it has a greater rolling effect than the irregularly shaped developer generated by the crushing method, etc., and slips through without being caught inside the nip To go.

Therefore, the external additive used in the present invention has an average particle size of 0.005 to 0.05 for improving fluidity.
Particles having a particle size of 0.1 to 1.0 [mu] m and having a charge amount of several [mu] C / g, which are hard and have a high polishing effect, using fine particles of 0% and having a large charge amount of approximately 100 [mu] C / g as an adhesive. Was used as a flocculant. As the adhesive, silica, titanium oxide, aluminum oxide, or the like is used. These may be surface-treated with silicone oil or the like. As a coagulant, silicon oxide, aluminum oxide, cerium oxide, germanium oxide, zinc oxide, tin oxide, zirconium oxide, molybdenum oxide, tungsten oxide, strontium oxide, boron oxide, silicon nitride, calcium titanate, magnesium titanate, titanium Powders such as strontium acid, phosphotungstic acid, phosphomolybdic acid, calcium carbonate, magnesium carbonate and aluminum carbonate may be mentioned.

Since the adhesive has a small particle size, it can not only be scraped off by the cleaning blade 2, but also strongly adheres to the image carrier 1 and the cleaning blade 2.
Although it inhibits the sliding properties of the blade nip and compresses effectively,
Due to the small particle size and the strength of its adhesion, it can hardly be scraped off by the cleaning blade 2. The coagulant alone has a low charge amount and therefore has a weak adsorption power, and has a particle size of about 1 μm, so that it is scraped well by the cleaning blade and does not stay at the edge of the cleaning blade 2. When these two particles are mixed, the adhesive is sandwiched in the blade nip, thereby compressing the blade nip and locally turning the cleaning blade to a size of about 1 μm, where an aggregating agent having a particle size of about 1 μm is sandwiched. Through the blade nip in very small amounts. Therefore, if a sufficient amount of the coagulant is externally added to and mixed with the developer, the amount of the coagulant is excessively supplied compared to the amount of the coagulant, and the coagulant stays at the edge of the cleaning blade 2 and acts as a wall for damping the developer. The surface can also be rubbed and cleaned.
The width of the external additive staying at the edge of the cleaning blade 2 is:
It is determined by the amount of the external additive in the developer and the setting of the cleaning blade 2. However, if the width is too narrow, the effect cannot be exhibited, and if the width is too wide, the amount of the coagulant retained is large, and the polishing amount of the image carrier 1 increases. 10 to 50 μm
It is appropriate to set the range.

Further, if fine particles for imparting the fluidity of the developer are used as the adhesive, the developer in the casing 3 can be prevented from being unbalanced, that is, the casing 3 can sufficiently receive the unnecessary developer. Can be used. By using hard particles as the coagulant, the surface of the image carrier 1 can be polished and cleaned by pressing the coagulant of the cleaning blade 2 with the coagulant.

A small amount of the coagulant remaining at the edge of the cleaning blade 2 must pass through the cleaning blade 2 in order to improve the slidability of the cleaning blade 2. However, if the amount of the coagulant slipping through is large, the amount of the coagulant to be mixed must be increased in order to stay. Similarly to the developer, the closer the coagulant is to a perfect sphere, the more difficult it is to block with a cleaning blade. Therefore, the ratio of the average major axis to the average minor axis is set to 0.1.
By setting the ratio to 8 or less, an external additive layer that further dams the developer can be stably present. On the other hand, if it is 0.5 or less, it becomes rod-shaped and the direction of the long axis is aligned when it stays, so that it is difficult to fill. Even if the hardness is higher, the polishing effect of the image carrier 1 is reduced.

Further, the surface of the image carrier 1 is rubbed and smoothed by the cleaning blade 2 by adopting a configuration in which the contact pressure of the cleaning blade 2 against the image carrier 1 is 10 to 20 gf / cm and the contact width is 50 to 100 μm. Thus, the cleaning device is characterized by maintaining high-quality image formation.

[0023]

FIG. 1 is a side sectional view showing the vicinity of a cleaning blade 2 of a cleaning apparatus according to an embodiment of the present invention, and is an enlarged view showing the vicinity of an edge of the cleaning blade 2 in FIG.

A transfer residual developer 5 generated at a transfer portion (not shown) and adhered to the surface of the image carrier 1 is scraped off by the cleaning blade 2 and received in the casing 3 by the rake sheet 4. In this embodiment, the particle size is 5 to 5.
A volume average particle diameter of 0.5 for a 10 μm spherical developer 5
0.3 to 2.0 μm highly cohesive particles (coagulant)
4.0% by weight, volume average particle size 0.0025 to 0.05
0.5-1.0% of highly adhesive particles (adhesive) of μm
In which the developer 5 mixed externally is used. Since the effect of the present invention depends on the difference in particle size, the same effect can be obtained with another particle size as long as the above ratio is satisfied.

As a structure of the cleaning device, a conventional system is used. As a material of the cleaning blade 2, polyurethane rubber is used. When measured with the apparatus used in this example, the contact pressure of the cleaning blade 2 against the image carrier 1 was 30 gf / cm, and the contact width L2 in the stationary state was 10 μm. Here, the contact width L2 was measured by using a transparent glass instead of the image carrier 1, pressing the cleaning blade 2 statically, and observing from the opposite side with an optical microscope. As the external additive 6 used in this example, strontium titanate classified to have an average particle size of 1.0 μm and silica fine particles having an average particle size of 0.01 μm were externally added to the developer 5 and mixed. Here, strontium titanate has a Mohs hardness of 5 or more and has a polishing effect. Further, the silica fine particles have an effect of imparting fluidity of the developer by being externally added to and mixed with the developer.

The image carrier and developer used to verify the present invention are as follows. As the image carrier, a titanyl phthalocyanine pigment was used as a charge generation layer, and bisphenol Z was used.
OPC coated with polycarbonate as charge transport layer
Although the photoconductor is used, an A-Si photoconductor or a Se photoconductor may be used. Further, the spherical developer uses a toner obtained by a suspension polymerization method comprising a core in which an ester-based wax is included, a resin layer having styrene-butyl acrylate and a surface layer having styrene-polyester, but the production method is limited. Not something.

The photosensitive drum of the image carrier thus produced was mounted on a copier in which the cleaning device of the present invention was modified, and a paper passing durability test was conducted at a temperature of 24 ° C. and a relative humidity of 55%. Table 1 shows the results of the image evaluation.

[0028]

[Table 1]

Experimental Result 1 (Durability test was performed on each developer with a solid white image and a solid black image) According to this configuration, only the tip of the cleaning blade 2 was slightly turned up by the adhesive and compressed. Only the flocculant selectively stays in the wedge-shaped space.

The amount of the adhesive is desirably 0.5 to 1.0% by weight based on the amount of the developing agent so that the cleaning blade is turned up to the extent that only the abrasive is removed without removing the developing agent. If the amount of the abrasive is too large, the excess amount does not function as the abrasive, and is not necessary because it is discharged as waste toner, but also increases the cohesiveness of the developer and hinders the developability. It is required to be 4.0% by weight or less, preferably 3.0% by weight or less due to adverse effects such as adverse effects. 0.3% or more, preferably 1.5% by weight or more in order to obtain a sufficient developer damping effect is necessary.

In the above-described cleaning apparatus using the externally added developer 5, the width of the abrasive layer at the edge of the cleaning blade 2 is 10 to ensure that the cleaning blade 2 stably contacts the rotation of the image carrier 1. 50μ
m is appropriate.

If the thickness is 10 μm or less, the polishing agent is removed by the cleaning
Slip at the edge leads to poor cleaning. If the width is as large as 50 μm or more, the surface of the image carrier 1 is rubbed and rubbed with more abrasive to shorten the life of the image carrier 1 by polishing and abrasion. And the rubbing performance of the cleaning blade 2 is reduced. In this way, once the ink is accumulated, the coagulant layer is stably held at the edge of the cleaning blade 2, so that stable cleaning performance can be maintained for a long period of time.

Embodiment 2 This embodiment is characterized in that the ratio of the average minor axis to the average major axis of the coagulant is set to 0.5 to 0.8 in the same configuration as shown in Example 1.

As described in the first embodiment, by externally adding the adhesive and the coagulant to the developer 5, the developer itself becomes the image carrier 1.
It has the effect of scraping off residual deposits on the surface. However, if the coagulant to be retained near the edge of the cleaning blade 2 is also close to a true sphere similarly to the developer, the amount of slippage which contributes to improving the rubbing performance of the cleaning blade 2 on the image carrier 1 increases, and the retention gradually increases. The width decreases. Table 2
After a solid black image is formed on the sheet and the state of the developer in the vicinity of the blade nip is stabilized, 1000
The width of the external additive layer when the image carrier 1 corresponding to zero sheets is rotationally driven is shown.

The measurement is a result obtained by using a transparent cylindrical photosensitive drum as the image carrier 1 and visually observing the photosensitive drum through the photosensitive drum in a stationary state after the experiment. The roundness of the flocculant was determined as the ratio of the average of the maximum diameter (average major axis) to the average of the minimum diameter (average minor axis) when 100 particles were observed with an electron microscope and sampled. The flocculant used was
It was obtained by a strontium titanate pulverization method, and the roundness was changed depending on the pulverization time and strength.

[0036]

[Table 2]

Experimental Results 2 As shown in Table 2, when the roundness of the flocculant retained near the blade edge was changed, if the roundness was larger than 0.8, the amount of the flocculant slipped through increased, and a long-term new If no coagulant is present, stable cleaning performance cannot be obtained. If it is smaller than 0.5, the function of the coagulant layer which should be filled and exhibited near the edge does not appear, and does not contribute to cleaning.

As a result, stable cleaning performance over a longer period can be maintained.

Embodiment 3 In this embodiment, a cleaning device using a spherical developer 5 in which a coagulant and an adhesive are externally added and mixed as described in Embodiment 1 is applied to the image carrier 1 of the cleaning blade 2. The feature is that the contact is performed so that the contact pressure is 10 to 20 gf / cm and the contact width in the stationary state is 50 to 100 μm.

As described in the first embodiment, by externally adding the adhesive and the coagulant to the developer 5, the developer itself becomes the image carrier 1.
It has the effect of scraping off residual deposits on the surface. Accordingly, it is possible to reduce the load of the contact of the cleaning blade 2 which is one of the causes of the rubbing damage to the image carrier 1 due to long-term use. Table 2 shows the evaluation of the contact condition of the cleaning blade 2 and the cleaning performance.

[0041]

[Table 3]

Experimental Result 3 (The contact pressure and contact width of the cleaning blade were measured at rest.) First, the effect of scraping the surface of the image carrier 1 by the cleaning blade 2 itself can be reduced. That is, by reducing the contact pressure of the cleaning blade 2, it is possible to prevent the damage due to the rubbing damage on the image carrier 1 from being further deepened. Specifically, 10
If it is not less than gf / cm, it is possible to scrape off residual deposits on the image carrier 1. A contact pressure exceeding 20 gf / cm or more is not appropriate because it not only promotes rubbing damage on the image carrier 1 but also causes blade turning. Here, as the contact pressure of the cleaning blade, it is desirable to select the lowest pressure that can obtain the required cleaning performance.

Further, since the present configuration has a higher effect of scraping the image carrier 1 than the case where the cleaning blade 2 abuts only on the image carrier 1, the developer 5 and the like sandwiched inside the blade nip are removed. In order to eliminate this, the contact width of the cleaning blade 2 to the image carrier 1 can be increased. As a conventional technique, the above-described configuration in which the sponge roller serving as the cleaning auxiliary member is disposed on the upstream side of the cleaning blade 2 promotes smoothing by rubbing the image carrier 1 with a wide surface. It is difficult for the blade to carry the same effect by cleaning the image carrier 1 only with the edge of the cleaning blade 2.

However, in the present configuration having the cleaning effect by the coagulant 6, by providing the abutting portion of the cleaning blade 2 having a wide area, only the tip of the blade nip is locally turned up and the abrasive is The other blade nip functions as a member rubbing the surface of the image carrier 1. By rubbing and smoothing the surface of the image carrier 1 in this manner, the generated rubbing damage can be removed. Specifically, as shown in the embodiment, in the conventional example, the contact width of the cleaning blade 2 with the image carrier 1 in the stationary state was 10 μm. This is to prevent the developer 5 from being interposed and adhered onto the image carrier 1 to contaminate the surface of the image carrier 1. However, in this configuration, since the external additive has the effect of scraping and the cleaning property is improved, the contact width L2 of the cleaning blade 2 is set to 100
No problem such as contamination on the image carrier 1 occurred even when the thickness was μm. Further, even when rubbing damage occurs on the image carrier 1 used for a long period of time, it is possible to rub the damage and smooth it. If the contact width L2 of the cleaning blade 2 is 50 μm or less, the scraping effect is low,
The extent of rubbing damage is worse.

Thus, the structure shown in the first embodiment suppresses the rubbing damage generated on the surface of the image carrier 1 and smoothes the surface, which is useful for obtaining a high-quality image for a longer period of time.

[0046]

As described above, according to the present invention,
In order to remove the transfer residual developer 5 on the image carrier 1 of the image forming apparatus using the spherical developer 5 with the cleaning blade 2, the volume average particle diameter in the developer 5 is 5 to 50% of the developer.
And a volume average particle diameter of the developer of 0.05 to 0.5
By externally adding and mixing an adhesive of 0%, it is easy to scrape off the spherical developer 5 which is usually difficult to clean, thereby obtaining advantages such as easy transfer to a transfer material. Of the cleaning blade 2 to reduce the scraping force of the surface of the image carrier 1 due to the above, thereby suppressing the rubbing damage on the surface of the image carrier 1 and further suppressing the rubbing damage generated on the surface of the image carrier 1. Carrier 1
Thus, the width of the contact portion can be widened, the rubbing damage on the surface of the image carrier 1 is small, and this greatly contributes to maintaining a high-quality image for a long period of time.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a cleaning device according to an embodiment of the present invention.

FIG. 2 is a side sectional view of a known cleaning device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image carrier 2 Cleaning blade 3 Casing 4 Rake sheet 5 Developer A Image carrier moving direction L1 External additive accumulation width L2 Cleaning blade contact width

Claims (6)

[Claims] 1. A cleaning device for an image forming apparatus, wherein a developer remaining on an image carrier is removed by a cleaning blade in contact with the image carrier. Is 5 to 50 of the developer
% Of particles having high cohesiveness of 0.3 to 4.0% by weight, and particles having a volume average particle size of 0.05 to 0.50% of the developer having a high adhesiveness of 0.5 to 1.0% by weight. And the mixed particles are accumulated at a width of 10 to 50 μm on the upstream side in the moving direction of the image carrier at a position where the cleaning blade comes into contact with the image carrier, thereby attaching the surface of the image carrier. A cleaning device for removing a kimono. 2. An abrasive having a Mohs hardness of 5 or more is used as said highly cohesive particles.
A cleaning device according to claim 1. 3. The cleaning apparatus according to claim 1, wherein a fluidity-imparting agent is used as the strongly adherent particles. 4. The cleaning apparatus according to claim 1, wherein the particles having a high cohesiveness have a ratio of an average minor axis to an average major axis of 0.5 to 0.8. 5. The cleaning blade is brought into contact with the image carrier such that the contact pressure of the cleaning blade against the image carrier is 10 to 20 gf cm, and the contact width in a stationary state is 50 to 100 μm. Claim 1,
5. The cleaning device according to 2, 3, or 4. 6. The cleaning device according to claim 1, wherein a toner having a volume average particle diameter of 4 to 10 μm obtained by a suspension polymerization method is used as a developer.